{"id":411,"date":"2017-02-24T21:58:26","date_gmt":"2017-02-24T19:58:26","guid":{"rendered":"http:\/\/sv1qzk.gr\/?p=411"},"modified":"2017-02-26T20:53:56","modified_gmt":"2017-02-26T18:53:56","slug":"countdown-timer-with-arduino","status":"publish","type":"post","link":"https:\/\/sv1qzk.gr\/index.php\/2017\/02\/24\/countdown-timer-with-arduino\/","title":{"rendered":"Countdown timer with Arduino"},"content":{"rendered":"

The need arose a construction of countdown timer. My first thought was to create\u00a0something, using a NIDRUINO (equivalent of Arduino UNO) that existed in my stock…
\nTo be able to have the adjustment and display parameters I use\u00a0the module:\u00a0LCD 1602 \u00a02×16<\/a><\/span>\u00a0which is accompanied by a number of push buttons for easy management of this where I wanted to construct.\u00a0Unfortunately, this module does not directly output analog and digital ports so add to the standby holes, single row breakaway male pins like that:\u00a0http:\/\/www.ebay.com\/itm\/10pc-black-40pin-2-54mm-Single-Row-Breakaway-Male-Pin-Header-for-Arduino-uno-R3-\/281773614793?<\/a>\u00a0to be able easily get some of the available ports (A0,A1,A2,A3,A4,D2,D3).\"\"<\/p>\n

<\/p>\n

The LCD 1602 module use the following analog and digital ports:<\/p>\n\n\n\n\n\n\n\n\n\n\n
Analog 0<\/span><\/td>\nButtons (select, up, right, down and left)<\/span><\/td>\n<\/tr>\n
Digital 4<\/span><\/td>\nDB4<\/span><\/td>\n<\/tr>\n
Digital 5<\/span><\/td>\nDB5<\/span><\/td>\n<\/tr>\n
Digital 6<\/span><\/td>\nDB6<\/span><\/td>\n<\/tr>\n
Digital 7<\/span><\/td>\nDB7<\/span><\/td>\n<\/tr>\n
Digital 8<\/span><\/td>\nRS (Data or Signal Display Selection)<\/span><\/td>\n<\/tr>\n
Digital 9<\/span><\/td>\nEnable<\/span><\/td>\n<\/tr>\n
Digital 10<\/span><\/td>\nBacklit Control<\/span>
\n HIGH = Backlight on<\/span>
\n LOW = Backlight off<\/span>
\n Use PWM signal to control brightness<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

And the code for the function as a countdown timer…
\nI use one buzzer (YL-44) in digital port 2 for sound alarm<\/p>\n

\/\/ Countdown Timer
\n\/\/ Vlassis Christodoulopoulos 2017
\n<\/span>
\n#include <LiquidCrystal.h><\/span><\/p>\n

LiquidCrystal lcd(8, 9, 4, 5, 6, 7); \u00a0 \/\/ ports used from\u00a0LCD panel<\/span>
\nint lcd_key = 0;<\/span>
\nint adc_key_in = 0;<\/span>
\nint backlight = 10;<\/span>
\nlong tim = 0;<\/span>
\nlong x = 0;<\/span>
\nlong s;<\/span>
\nlong thou = 0;<\/span>
\nlong tmin = 0;<\/span>
\nlong tsec = 0;<\/span>
\nint ct = 0; \/\/change tag (ct) 1 for Hours, 2 for min, and 3 for sec<\/span>
\nint buzzer = 2;<\/span>
\nint bl = 1;<\/span>
\nint ot = 2; \u00a0\/\/default 2 seconds<\/span>
\nint otf = 0; \u00a0\/\/ flag for editing ON TIME time<\/span><\/p>\n

#define RIGHT 0<\/span>
\n#define UP 1<\/span>
\n#define DOWN 2<\/span>
\n#define LEFT 3<\/span>
\n#define SELECT 4<\/span>
\n#define NONE 5<\/span><\/p>\n

int read_LCD_buttons() \u00a0\/\/ read the buttons<\/span>
\n{<\/span>
\n adc_key_in = analogRead(0); \/\/ read the value from the sensor<\/span>
\n \/\/ my buttons when read are centered at these valies: 0, 144, 329, 504, 741<\/span>
\n \/\/ we add approx 50 to those values and check to see if we are close<\/span>
\n if (adc_key_in > 1000) return NONE; \/\/ We make this the 1st option for speed reasons since it will be the most likely result<\/span>
\nif (adc_key_in < 50) return RIGHT;<\/span>
\n if (adc_key_in < 250) return UP;<\/span>
\n if (adc_key_in < 450) return DOWN;<\/span>
\n if (adc_key_in < 650) return LEFT;<\/span>
\n if (adc_key_in < 850) return SELECT;<\/span><\/p>\n

return NONE; \u00a0\/\/ when all others fail, return this…<\/span>
\n}<\/span><\/p>\n

void buzzering(int t, int l)<\/span>
\n{<\/span>
\n for (int to = (t \/ (2 * l)); to >= 0; –to) \/\/ length loop 2*l milliseconds<\/span>
\n {<\/span>
\n digitalWrite(buzzer, LOW);<\/span>
\n delay(l);<\/span>
\n digitalWrite(buzzer, HIGH);<\/span>
\n delay(l);<\/span>
\n }<\/span>
\n}<\/span><\/p>\n

void setup()<\/span>
\n{<\/span>
\n pinMode(buzzer, OUTPUT);<\/span>
\n pinMode(backlight, OUTPUT);<\/span>
\n digitalWrite(buzzer, HIGH);<\/span>
\n digitalWrite(backlight, HIGH);<\/span>
\n lcd.begin(16, 2); \/\/ start the library<\/span>
\n lcd.setCursor(0, 0);<\/span>
\n lcd.print (“Ver4 Vlassis (c)”);<\/span>
\n lcd.setCursor(0, 1);<\/span>
\n lcd.print (“Initialising “);<\/span>
\n for (int x = 1; x <= 4; x++)<\/span>
\n {<\/span>
\n delay(1000);<\/span>
\n lcd.print(“.”);<\/span>
\n }<\/span>
\n lcd.setCursor(0, 0);<\/span>
\n lcd.print (” “);<\/span>
\n lcd.setCursor(0, 1);<\/span>
\n lcd.print (” “);<\/span>
\n}<\/span><\/p>\n

void loop()<\/span>
\n{<\/span>
\n lcd_key = read_LCD_buttons(); \u00a0\/\/ read the buttons<\/span>
\n delay(100);<\/span>
\n switch (lcd_key) \u00a0\/\/ depending on which button was pushed, we perform an action<\/span>
\n {<\/span>
\n case RIGHT:<\/span>
\n {<\/span>
\n otf = 1;<\/span>
\n lcd.setCursor(0, 1);<\/span>
\n lcd.print(“ON TIME “);<\/span>
\n lcd.setCursor(10, 1);<\/span>
\n lcd.print(ot);<\/span>
\n lcd.print(“s”);<\/span>
\n break;<\/span>
\n }<\/span>
\n case LEFT:<\/span>
\n {<\/span>
\n otf = 0;<\/span>
\n if (ct > 3) {<\/span>
\n ct = 1;<\/span>
\n } else {<\/span>
\n ++ct;<\/span>
\n }<\/span>
\n lcd.setCursor(0, 1);<\/span>
\n if (ct == 1 )<\/span>
\n {<\/span>
\n lcd.print(“Change HOURS “);<\/span>
\n delay(100);<\/span>
\n }<\/span>
\n if (ct == 2 )<\/span>
\n {<\/span>
\n lcd.print(“Change MINUTES “);<\/span>
\n delay(100);<\/span>
\n }<\/span>
\n if (ct == 3 )<\/span>
\n {<\/span>
\n lcd.print(“Change SECONDS “);<\/span>
\n delay(100);<\/span>
\n }<\/span>
\n break;<\/span>
\n }<\/span>
\n case UP:<\/span>
\n {<\/span>
\n if (otf == 1)<\/span>
\n {<\/span>
\n delay(100);<\/span>
\n ++ot;<\/span>
\n lcd.setCursor(10, 1);<\/span>
\n lcd.print(ot);<\/span>
\n lcd.print(“s “);<\/span><\/p>\n

}<\/span>
\n else<\/span>
\n {<\/span>
\n if (ct == 1)<\/span>
\n {<\/span>
\n ++thou;<\/span>
\n }<\/span>
\n if ( thou > 99) {<\/span>
\n thou = 0;<\/span>
\n }<\/span>
\n if (ct == 2)<\/span>
\n {<\/span>
\n ++tmin;<\/span>
\n }<\/span>
\n if ( tmin > 59) {<\/span>
\n tmin = 0;<\/span>
\n }<\/span>
\n if (ct == 3)<\/span>
\n {<\/span>
\n ++tsec;<\/span>
\n }<\/span>
\n if ( tsec > 59) {<\/span>
\n tsec = 0;<\/span>
\n }<\/span><\/p>\n

tim = thou * 3600 + tmin * 60 + tsec;<\/span>
\n }<\/span>
\n break;<\/span>
\n }<\/span>
\n case DOWN:<\/span>
\n {<\/span>
\n if (otf == 1)<\/span>
\n {<\/span>
\n delay(100);<\/span>
\n –ot;<\/span>
\n lcd.setCursor(10, 1);<\/span>
\n lcd.print(ot);<\/span>
\n lcd.print(“s “);<\/span>
\n }<\/span>
\n else<\/span>
\n {<\/span>
\n if (ct == 1)<\/span>
\n {<\/span>
\n –thou;<\/span>
\n }<\/span>
\n if ( thou < 0) {<\/span>
\n thou = 99;<\/span>
\n }<\/span>
\n if (ct == 2)<\/span>
\n {<\/span>
\n –tmin;<\/span>
\n }<\/span>
\n if ( tmin < 0) {<\/span>
\n tmin = 59;<\/span>
\n }<\/span>
\n if (ct == 3)<\/span>
\n {<\/span>
\n –tsec;<\/span>
\n }<\/span>
\n if ( tsec < 0) {<\/span>
\n tsec = 59;<\/span>
\n }<\/span>
\n tim = thou * 3600 + tmin * 60 + tsec;<\/span>
\n }<\/span>
\n break;<\/span>
\n }<\/span>
\n case SELECT:<\/span>
\n {<\/span>
\n lcd.setCursor(0, 0);<\/span>
\n analogWrite(backlight, 30); \u00a0\/\/ Change background light to minimum for countdown mode…<\/span>
\n lcd.print(“COUNTDOWN… “);<\/span>
\n lcd.setCursor(0, 1);<\/span>
\n lcd.print(” “);<\/span>
\n for (long x = tim; x > 0; x–)<\/span>
\n {<\/span>
\n lcd.setCursor(0, 1);<\/span>
\n s = x \/ 3600;<\/span>
\n lcd.print (s);<\/span>
\n lcd.print (“h “);<\/span>
\n s = x – (s * 3600);<\/span>
\n lcd.print (s \/ 60);<\/span>
\n lcd.print (“m “);<\/span>
\n lcd.print (s % 60 );<\/span>
\n lcd.print (“s “);<\/span>
\n delay(996); \u00a0\/\/ Change this value for time base calibration purpose<\/span>
\n }<\/span>
\n lcd.setCursor(0, 1);<\/span>
\n lcd.print(“BEEP… “);<\/span>
\n buzzering (ot * 1000, 50); \u00a0\/\/ sec * milliseconds<\/span>
\n analogWrite(backlight, 1200); \u00a0\/\/ Change background light to maximum for edit mode…<\/span>
\n lcd.setCursor(0, 1);<\/span>
\n lcd.print(” “);<\/span>
\n lcd.setCursor(0, 0);<\/span>
\n lcd.print(” “);<\/span>
\n }<\/span>
\n case NONE:<\/span>
\n {<\/span>
\n lcd.setCursor(0, 0);<\/span>
\n lcd.print(“TIME”);<\/span>
\n lcd.setCursor(5, 0);<\/span>
\n lcd.print(thou);<\/span>
\n lcd.print(“h “);<\/span>
\n lcd.print(tmin);<\/span>
\n lcd.print(“m “);<\/span>
\n lcd.print(tsec);<\/span>
\n lcd.print(“s”);<\/span>
\n lcd.print(” “);<\/span>
\n break;<\/span>
\n }<\/span>
\n }<\/span><\/p>\n

}<\/span><\/p>\n

The code is not the best (optimized)… but can be a basis for making many improvements and additions!
\n\"\"
\n\"\"
\n\"\"
\n\"\"
\n\"\"
\n\"\"<\/p>\n

Push buttons
\n<\/span>Left\u00a0<\/span> = \u00a0(edit mode) -> change hours -> change minutes -> change seconds
\nUp<\/span>\u00a0 = Increase value
\nDown\u00a0<\/span> = \u00a0Decrease value
\nRight<\/span>\u00a0 = \u00a0Change activation time value with Up<\/span>, Down<\/span> buttons
\nRst<\/span>\u00a0 = \u00a0Reset
\nSelect<\/span>\u00a0 = \u00a0Go to countdown mode<\/p>\n","protected":false},"excerpt":{"rendered":"

The need arose a construction of countdown timer. My first thought was to create\u00a0something, using a NIDRUINO (equivalent of Arduino UNO) that existed in my stock… To be able to have the adjustment and display parameters I use\u00a0the module:\u00a0LCD 1602 \u00a02×16\u00a0which is accompanied by a number of push buttons for easy management of this where … Continue reading Countdown timer with Arduino<\/span> →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[12],"tags":[],"class_list":["post-411","post","type-post","status-publish","format-standard","hentry","category-arduino"],"_links":{"self":[{"href":"https:\/\/sv1qzk.gr\/index.php\/wp-json\/wp\/v2\/posts\/411","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sv1qzk.gr\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sv1qzk.gr\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sv1qzk.gr\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sv1qzk.gr\/index.php\/wp-json\/wp\/v2\/comments?post=411"}],"version-history":[{"count":38,"href":"https:\/\/sv1qzk.gr\/index.php\/wp-json\/wp\/v2\/posts\/411\/revisions"}],"predecessor-version":[{"id":484,"href":"https:\/\/sv1qzk.gr\/index.php\/wp-json\/wp\/v2\/posts\/411\/revisions\/484"}],"wp:attachment":[{"href":"https:\/\/sv1qzk.gr\/index.php\/wp-json\/wp\/v2\/media?parent=411"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sv1qzk.gr\/index.php\/wp-json\/wp\/v2\/categories?post=411"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sv1qzk.gr\/index.php\/wp-json\/wp\/v2\/tags?post=411"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}